On Thu, Sep 07, 2023 at 09:11:34 +0200, Martin Kletzander wrote:
> On Wed, Sep 06, 2023 at 06:34:42PM +0300, Dmitry Frolov wrote:
> > Reviewing the sources, I found, that
> > in function lxcContainerMountAllFS() pointers
> > vmDef->fss[i]->src and vmDef->fss[i]->src->path
> > are checked for NULL after dereferencing in
> > VIR_DEBUG() macro.
> >
> > Fixes: 57487085dc ("lxc: don't try to reference NULL when mounting filesystems")
> > ---
> > src/lxc/lxc_container.c | 6 ++++--
> > 1 file changed, 4 insertions(+), 2 deletions(-)
[...]
> > if (lxcContainerResolveSymlinks(vmDef->fss[i], false) < 0)
> > return -1;
> >
> > - if (!(vmDef->fss[i]->src && vmDef->fss[i]->src->path &&
> > - STRPREFIX(vmDef->fss[i]->src->path, vmDef->fss[i]->dst)) &&
> > + if (!STRPREFIX(vmDef->fss[i]->src->path, vmDef->fss[i]->dst) &&
> > lxcContainerUnmountSubtree(vmDef->fss[i]->dst, false) < 0)
>
> ... here it only skips the unmount in such case. That makes sense
> because for example tmpfs does not have a source path, only the
> destination and the mount that is not visible in the context here would
> not only be skipped as well, but the whole starting of a domain would
> fail.
>
> Instead of this patch, you could just conditionally change the
> VIR_DEBUG() to report what's actually happening.
And we have a handy NULLSTR() macro for that case.
>
> > return -1;
> >
> > --
> > 2.34.1
> >
